With Gaia Vince's take on indium futures having proven mistaken, it's interesting to see Tim Worstall's look last year at availability of another rare metal: tellurium, which finds a major application in solar panels. Tim has crunched the numbers and worked out just how much of it we have at current usage rates:

So, even for [tellurium] one of the rarest metals on the planet we seem to have a million year supply of it. We could, at this point, say that the environmentalists are obviously correct, there is a risk of running out and we’d better do something about it. But worrying about what happens in a million years time is really a very slightly silly thing to be worrying about: the odds that our species will still be here at that time are pretty low, let alone the idea that we’ll be reliant upon Cd/Te solar panels.

So, no, we don’t in fact face an actual shortage of atoms of the right elements. You’re welcome to try the same calculations with any other element you choose and while you might come up with different time spans, the basic conclusion will be the same: we simply don’t have a shortage of elements.

Tim has also picked up on the indium story here, and adds these further thoughts by email:

A thought that occured to me this morning.

If you look at the USGS thing they say that the lead/zinc ores often only have 1 ppm of indium.

At current indium prices of course we don't try to extract it.

However, look over at gold mining: 1 gramme per tonne, 1 g Au per tonne rock is considered quite a nice ore these days. Certainly worth processing.

Sure, gold is $55,000 a kg, not the $550 per kg of indium.

But that just shows it's an economic point, not a technical or resource limitaiton one.

Reader Comments (23)

Not a metal, obviously, but what about helium? I've read a number of articles in recent years about a looming shortage of the stuff - although I'm told it's obtainable where oil and gas are drilled for, so could the shale gas revolution also provide a future bonanza of helium?

I think that some gas wells, particularly in the USA, have quite a lot of helium and it's worth recovering. Most natural gas has some. I haven't heard that shale gas has a particularly high content.

Presumably what will happen is that if easily accessible sources decline, other sources start to be attractive. The prices rises, it ceases to be used for things such as filling balloons, industrial processes which have to use it pay more and are more careful about waste and recovery etc., or develop substitutes. Much the same as any other extracted resource.

The argument is not that we will ever run out of any of the rare earth metals. It is that we will run out of economic deposits that are necessary to keep production levels increasing. From what I can see that is still a reasonable point.

We need to keep in mind that when whale oil became too expensive to keep production growing we did not go out and find more whales or kill all of the whales that were left. We simply figured out how to find viable substitutes. Unless there is a breakthrough in processing it is looking as if we are going to have to do the same with some of the rare earth uses.

And yes, there are distinctions to be made here. The rare earths are not rare (nor earths) and they are scandium, yttrium and the 15 lanthanides (Ce, La, Nd, Tb etc). There are two problems with these metals. One, for economic reasons, China currently dominates production. That's changing and will be gone in a decade. The second is that there's plenty of ores around, 15 minutes on google and you could find sufficient ores to double global production (hint, bauxite and titanium sands). The problem is really with separating them, one from each other., For some of them, to get a reasonable purity, you have to do 1,000 iterations of solvent extraction.

OK, then there's rare metals like indium. Not a rare earth, the priblem is simply that while there's not a lot about relative to, say iron. Then there's minor metals, which are always produced as co-products. You'll note that indium is both a rare and a minor metal but not a rare earth. Yttrium is not a rare metal nor (in the strict sense) a minor metal but it is a rare earth. Lutetium is a rare, minor and rare earth metal.

Tellurium and indium figure not at all in conventional ( silicon ) PV manufacture , and the very nature of the alternative thin film PV materials in which it does figure, like CdInTe, would somewhat limit demand .

That said, the supply remains volatile because there are no primary mines or ore minerals of either element, - the played out gold mines of Telluride Colorado no longer provide enough solar cell materiel to power a film festival, leaving Fijian gold miners to take up the slack.

Paul Soros' clever revival of zinc mining in Bolivia to get silver may also ease the indium supply.

Many important superconducting instruments in physics and chemistry labs would be screwed without liquid helium to keep them cold. The US did have a strategic reserve for Helium, but I read some place that they sold it, disposed of it, or decreased it. Probably because the supply is still relatively large from natural gas sources. I was once a student in a chemistry department where the helium was recycled by a large underground pipe back to the physics building some distance away. It's OK Tim Worstall, I'll hold the 'pedantry fort' until you get back.Tellurium is often described not as a metal, but as one of the semi-conducting non-metals, or metalloids.

Tim W - nice synopsis (I've worked on many of the elements you mentioned).

I'll add one thing, which is that brain power is not running out. In the case of indium the main use is for transparent touch sensitive screens. This already has seen advances in alternatives using organic conductors and materials like graphene. If indium price rises too high, you can bet your boots these will come into the market.

"Many important superconducting instruments in physics and chemistry labs would be screwed without liquid helium to keep them cold." Good grief, are people still fannying around with superconductivity? I can remember when imminent breakthroughs in that field were promised to bring us ... oh, I don't know, free watermelons or something: something nice and wonderful anyway.

It's not the million years that is funny, it is the enviro folks' complete failure as always to recognise that there is a perfectly good mechanism in place which prospectively recognises scarcity and deals with it far, far better than anything the enviro folks have ever proposed. And that mechanism is called: a market.

dearieme: "Good grief, are people still fannying around with superconductivity? I can remember when imminent breakthroughs in that field were promised to bring us ... oh, I don't know, free watermelons or something: something nice and wonderful anyway."

I assure you they are not "fannying around" with superconductivity. These are real uses OF and WITH supercooled objects often magnets and ultra-sensitive detectors. Not basic research into superconductivity.An example: Without helium cooled Nuclear Magnetic Resonance (NMR) instruments, modern synthetic chemistry and structural analysis would grind to a standstill. The pharmaceutical industry would not just be "screwed" they would be "well and truly f***ing screwed".

While you are quiet right about the usefulness of super conducting magnets, which include the LHC at Cern, there were other proposed uses for them that were in the Popular Science press.

I think dearieme was talking about how "high temperature" superconducting power lines and such were going to drastically save money, power, and other hand waving done about five to ten years ago. Much like the destruction of all the coral reefs of the world by voracious star fish, such claims have quietly disappeared.

Sigh... and you don't think you would get even bigger bang-for-the-buck (or pound, or euro) by putting that high-performance superconducting generator in a conventional power plant, where all the cryogenics (etc) could be easily accessed, rather than being up on a slender pole 25 storeys in the air? I wonder about the technology in any event - existing generators for even small scale hydro plants (say 35-40 MW units) are already ~98% efficient: while the last 1% or 2% is worth something, on generator efficiency we are well into the diminishing returns range. I don't know much about wind turbines, so perhaps GE has removed a limiting condition of some sort.

The several whole Tesla field of the suoerconducting magnets allows air gap induction , eliminating the pole piece eddy losses experienced with NdFeB permanent magnets. Similar improvements might carry over to hydro systems.

"Good grief, are people still fannying around with superconductivity? I can remember when imminent breakthroughs in that field were promised to bring us ... oh, I don't know, free watermelons or something: something nice and wonderful anyway."

Just imagine one of those 15 MW monsters sitting on its creaky foundation (in need of grouting, apparently) 25 stories about the sea, whacking the seagulls right and left, with an intrepid sea captain trying to deliver a boat load of liquid helium during a gale.

Oh, yes, -- I can see it now. We should call the wind turbine Moby Dick because it would certainly be a great white whale.

Perhaps - but as indicated, generators in hydro systems are already at ~98% efficiency. Getting another 2% energy and capacity "for free" (the limiting case) would be nice, but it's not a game-changer.